A spokesman for U.S. Attorney Ronald C. Machen Jr., seen in 2012, said he will take a careful approach to future marijuana prosecutions. (Matt McClain/For The Washington Post)

When a House Oversight subcommittee invited law enforcement officials to testify Friday on the District’s new marijuana decriminalization law, one key lawman was conspicuously absent: U.S. Attorney Ronald C. Machen Jr., whose office will have to decide how to handle marijuana possession cases that will no longer qualify as criminal offenses under District law but will remain prosecutable under federal law.

The witnesses who did testify Friday made clear that Machen and his successors as the city’s top federal prosecutor will play a central role in how decriminalization plays out in the District. And while Machen himself did not testify, his office gave the first indication of how it plans to handle minor marijuana arrests under the new D.C. law.

In a statement to The Washington Post, the office said it will charge marijuana possession carefully, if not reluctantly: “We will assess each case on an individualized basis, weighing all available information and evidence, consistent with Justice Department enforcement priorities and the need to use our limited investigative and prosecutorial resources to address the most significant threats to public safety,” said spokesman William Miller, who added that prosecutors “rely heavily on diversion programs in our local marijuana prosecutions, and would likely do the same with respect to federal offenses.”

Consider that as a supplement to the Capitol Hill testimony: David A. O’Neil, the acting chief of the Justice Department’s criminal division, said the feds plan to maintain the same policy toward the District as toward states that have liberalized their marijuana laws — meaning the local U.S. attorney will have significant discretion in handling cases in a way that comports with the department’s list of eight enforcement priorities. (Of particular import in the District is this one: “Preventing marijuana possession or use on federal property.”) And Robert MacLean — acting chief of the U.S. Park Police, which makes more marijuana arrests than any other law enforcement agency besides the Metropolitan Police Department — said his department would “work closely” with Machen’s office to “determine our future enforcement options.”

Should the new law pass its congressional review period in the coming weeks, D.C. police will start issuing non-criminal citations to persons caught possessing an ounce of weed or less, meaning prosecutors won’t be presented with an alleged crime to charge. But because possession will remain a federal crime, arrests made by the Park Police, Capitol Police, Secret Service and many other law enforcement agencies will still be presented to Machen’s office for prosecution.

While the vast majority of marijuana arrests in the District are made by D.C. police, arrests by other agencies are hardly rare. According to statistics compiled by the American Civil Liberties Union, nearly 400 marijuana arrests were made in 2010 by officers of other departments, and more than 80 percent of those arrests were for simple possession rather than more serious distribution or intent-to-distribute charges — suggesting that prosecutors will be faced on a daily basis with decisions on whether to charge arrestees under federal law for a offense that is not a local crime.

The statement from Machen’s office — particularly the reference to “the need to use our limited investigative and prosecutorial resources to address the most significant threats to public safety” — suggests that persons caught with small amounts of marijuana by federal law enforcement officers in the District will probably not have the book thrown at them. But nor can they rest assured that prosecutors will let them off entirely.

Here is Miller’s statement in full:

Under the new bill, smoking marijuana in public would remain a criminal offense, and so anyone who smokes marijuana on federal property could still be prosecuted under D.C. law. Individuals arrested for merely possessing, but not using, less than one ounce of marijuana on federal property would be presented to our office for potential prosecution under federal law. We will assess each case on an individualized basis, weighing all available information and evidence, consistent with Justice Department enforcement priorities and the need to use our limited investigative and prosecutorial resources to address the most significant threats to public safety. We rely heavily on diversion programs in our local marijuana prosecutions, and would likely do the same with respect to federal offenses.

Mike DeBonis covers Congress and national politics for The Washington Post. He previously covered D.C. politics and government from 2007 to 2015.

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